Statistical Analysis Stack Exchange
Statistical Analysis Stack Exchange

Questions tagged [distribution-identification]

Questions about recognizing a probability distribution from a figure, formula, or text description. Please use a specific, informative title.

Questions about recognizing a probability distribution from a figure are quite distinct from questions about formulas or text descriptions. As such, please take care to use an informative title to avoid filling the 'Related' section with questions that are actually unrelated.

Below are some useful resources for identifying a probability distribution:

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How to determine which distribution fits my data best?

I have a dataset and would like to figure out which distribution fits my data best. I used the fitdistr() function to estimate the necessary parameters to describe the assumed distribution (i.e. Weibull, Cauchy, Normal). Using those parameters I…
tobibo
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What distribution does my data follow?

Let us say that I have 1000 components and I have been collecting data on how many times these log a failure and each time they logged a failure, I am also keeping track of how long it took my team to fix the problem. In short, I have been recording…
Legend
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Does this distribution have a name? $f(x)\propto\exp(-|x-\mu|^p/\beta)$

It occurred to me today that the distribution $$ f(x)\propto\exp\left(-\frac{|x-\mu|^p}{\beta}\right) $$ could be viewed as a compromise between the Gaussian and Laplace distributions, for $x\in\mathbb{R}, p\in[1,2]$ and $\beta>0.$ Does such a…
Sycorax
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How do I figure out what kind of distribution represents this data on ping response times?

I've sampled a real world process, network ping times. The "round-trip-time" is measured in milliseconds. Results are plotted in a histogram: Ping times have a minimum value, but a long upper tail. I want to know what statistical distribution this…
Ian Boyd
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Distribution of the ratio of dependent chi-square random variables

Assume that $ X = X_1 + X_2+\cdots+ X_n $ where $X_i \sim N(0,\sigma^2)$ are independent. My question is, what distribution does $$ Z = \frac{X^2}{X_1^2 + X_2^2 + \cdots + X_n^2}$$ follow? I know from here that the ratio of two chi-squared random…
x0dros
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Name for a distribution between exponential and gamma?

The density $$f(s)\propto \frac{s}{s+\alpha}e^{-s},\quad s > 0$$ where $\alpha \ge 0$ is a parameter, lives between the exponential ($\alpha=0$) and $\Gamma(2,1)$ ($\alpha \to \infty$) distributions. Just curious if this happens to be an example of…
nth
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What kind of distribution does this have?

Currently I'm trying to figure out the distribution of the following: $X \sim \frac{\sqrt{n}}{\sqrt{Gamma(n,\beta)}}$ where the denominator follows a $Gamma(n,\beta)$ distribution. I've checked out these links: Square root of an inverse gamma…
BonnieKlein
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Distribution with a given moment generating function

As a follow-up to a question on a central limit theorem for independent random variables (r.v.) here, let $Y_j=-\log(1-V_j)$, where $V_j\sim\mbox{beta}(1-\sigma,j\sigma)$, $j\in\mathbb{N}^*$, $\sigma\in(0,1)$. The shifted sums…
julyan
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Identifying the following distribution

I have a distribution, which I initially assumed to be a Rayleigh, but it almost certainly isn't. Before I consider convolutions of various distributions, e.g. Rayleigh convolved with Boltzmann, Rayleigh convolved with Gaussian and so on, I was…
Q.P.
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Understanding the Cullen and Frey plot

I would like to figure out which distribution fits my data best. Here is the histogram of my data : I used the fitdistrplus package in R to try to find the best fit for my data. To get an idea of which family distribution to fit, I did…
Louna_DO
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Can anyone suggest a distribution for this histogram

I have some data and I am trying to identify its distribution. The nearest I can get is a skewed-Gaussian distribution, but I don't think it is. The data itself consists of 130000 points and is binned with the Freedman–Diaconis rule. I also tried…
Q.P.
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Name of a distribution similar to the exponential

for a simulation I'm using the continuous distribution $$F(x)=1-(1+x)e^{-cx} $$ for $x\geq 0$ with $c\geq 1$. Do you know if this distribution has a name?
Jo R
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What kind of distribution is this? (Number of stones until 2 are adjacent in a game of Go)

I've plotted the histogram of the number of stones required so that 2 are adjacent when randomly placed 1 by 1 on a goban (think of a 19x19 chessboard and I place pieces 1 by 1 until 2 are adjacent, not counting diagonals), after 10 million trials.…
untreated_paramediensis_karnik
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What kind of distribution is this "almost" uniformly distributed data for calls/week?

My supervisor asked me to find out which distribution represents a particular situation. I have a VoIP generator that generates calls "uniformly" distributed between callers. This means that the volume per caller distribution is "almost" uniformly…
Maurizio
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What is the name of this distribution?

I came across this: a categorical distribution with $K=10,000$ parameters (categories), and we take only few samples from this distribution, say $N=400$ (the point is $N < K$). Now, obviously, not all categories will show up in the sampled data, so…
John Deterious
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